Jay-Z, Justin Bieber, Chris Brown and Kayne West have been approached to join the 'Michael Forever' tribute concert.

The show marking the life of Michael Jackson - who passed away from acute Propofol intoxication in June 2009, as he was preparing to make a comeback - will take place on October 8 at the Stadium of Light in Cardiff, Wales, and his mother, Katherine, has asked some of the biggest stars in music to perform.

The elaborate invitations state: "My son was a fan of your work and it would be our pleasure to have you be a part of this historic event. The music will be provided by seasoned musicians including members of Michael's band.

"We would like you to select one of two of your favorite Michael Jackson songs to perform that day in honor of my son."

Of those invited, Kanye West is said to be on board for the event, as is British soul singer Craig David and Cee-Lo Green, whileChristina Aguilera is also said to be trying to make it.

Other stars, including Chris Brown, Justin Bieber and Bruno Mars have reportedly had to respectfully decline their invitations, due to scheduling conflicts.

More acts for the line up are expected to be confirmed in coming days. It is also expected that many of Michael's family members will take to the stage at the event.